Lens module

ABSTRACT

A lens module includes: a first lens having negative refractive power; a second lens having positive refractive power; a third lens having negative refractive power; a fourth lens having negative refractive power; a fifth lens of which an object-side surface is concave; and a sixth lens having one or more inflection points on an image-side surface thereof, wherein the first to sixth lenses are sequentially disposed from an object side of the lens module to an image side of the lens module.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/558,645 filed on Sep. 3, 2019, which is a continuation of U.S. patentapplication Ser. No. 14/942,346 filed on Nov. 16, 2015, now U.S. Pat.No. 10,451,842, which claims benefit of priority under 35 U.S.C. 119(a)of Korean Patent Application No. 10-2014-0175022 filed on Dec. 8, 2014,in the Korean Intellectual Property Office, the entire disclosures ofwhich are incorporated herein by reference for all purposes.

BACKGROUND 1. Field

The following description relates to a lens module having an opticalsystem including multiple lenses.

Description of Related Art

A conventional lens module mounted in a camera of a mobilecommunications terminal includes a plurality of lenses. For example, thelens module may include six lenses in order to configure an opticalsystem having high resolution.

However, when the optical system having high resolution is configuredusing the plurality of lenses as described above, a length (distancefrom an object-side surface of a first lens to an image plane) of theoptical system may be increased. In this case, it is difficult to mountthe lens module in a slim mobile communications terminal. Therefore, thedevelopment of a lens module having an optical system of decreasedlength is desirable.

For reference, Japanese Patent Publication No. JP2014-044250 A and U.S.Patent Application Publication No. US2014-0118844 A1 disclose lenses inthe related art.

SUMMARY

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

According to one general aspect, a lens module includes: a first lenshaving negative refractive power; a second lens having positiverefractive power; a third lens having negative refractive power; afourth lens having negative refractive power; a fifth lens of which anobject-side surface is concave; and a sixth lens having one or moreinflection points on an image-side surface thereof, wherein the first tosixth lenses are sequentially disposed from an object side of the lensmodule to an image side of the lens module.

The first lens may have a meniscus shape.

An object-side surface of the second lens may be convex.

An image-side surface of the second lens may be convex.

At least one of an object-side surface and an image-side surface of thethird lens is concave.

The fourth lens may have a meniscus shape.

An image-side surface of the fifth lens may be convex.

An object-side surface of the sixth lens may be convex.

The image-side surface of the sixth lens may be concave.

The refractive power of the first lens may be stronger than a refractivepower of the sixth lens.

According to another general aspect, a lens module comprises: a firstlens having negative refractive power; a second lens having positiverefractive power; a third lens of which an image-side surface isconcave; a fourth lens having refractive power; a fifth lens havingpositive refractive power, an object-side surface thereof being concave;and a sixth lens having negative refractive power and having one or moreinflection points on an image-side surface thereof, an object-sidesurface thereof being convex, wherein the first to sixth lenses aresequentially disposed from an object side of the lens module to an imageside of lens module.

The first lens may have a meniscus shape.

An image-side surface and an object-side surface of the second lens maybe convex.

An object-side surface of the third lens may be convex.

The fourth lens may have a meniscus shape.

An image-side surface of the fifth lens may be convex.

The image-side surface of the sixth lens may be concave.

The refractive power of the first lens may be stronger than therefractive power of the sixth lens.

Other features and aspects will be apparent from the following detaileddescription, the drawings, and the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a view of a lens module according to an example.

FIGS. 2A and 2B are graphs having curves which represent aberrationcharacteristics of the lens module illustrated in FIG. 1 .

FIG. 3 is a table illustrating characteristics of lenses illustrated inFIG. 1 .

FIG. 4 is a table representing conic constants and aspheric coefficientsof the lens module illustrated in FIG. 1 .

FIG. 5 is a view of a lens module according to another example.

FIGS. 6A and 6B are graphs having curves which represent aberrationcharacteristics of the lens module illustrated in FIG. 5 .

FIG. 7 is a table illustrating characteristics of lenses illustrated inFIG. 5 .

FIG. 8 is a table representing conic constants and aspheric coefficientsof the lens module illustrated in FIG. 5 .

FIG. 9 is a view of a lens module according to another example.

FIGS. 10A and 10B are graphs having curves which represent aberrationcharacteristics of the lens module illustrated in FIG. 9 .

FIG. 11 is a table illustrating characteristics of lenses illustrated inFIG. 9 .

FIG. 12 is a table representing conic constants and asphericcoefficients of the lens module illustrated in FIG. 9 .

FIG. 13 is a view of a lens module according to yet another example.

FIGS. 14A and 14B are graphs having curves which represent aberrationcharacteristics of the lens module illustrated in FIG. 13 .

FIG. 15 is a table representing characteristics of lenses illustrated inFIG. 13 .

FIG. 16 is a table representing conic constants and asphericcoefficients of the lens module illustrated in FIG. 13 .

Throughout the drawings and the detailed description, the same referencenumerals refer to the same elements. The drawings may not be to scale,and the relative size, proportions, and depiction of elements in thedrawings may be exaggerated for clarity, illustration, and convenience.

DETAILED DESCRIPTION

The following detailed description is provided to assist the reader ingaining a comprehensive understanding of the methods, apparatuses,and/or systems described herein. However, various changes,modifications, and equivalents of the methods, apparatuses, and/orsystems described herein will be apparent to one of ordinary skill inthe art. The sequences of operations described herein are merelyexamples, and are not limited to those set forth herein, but may bechanged as will be apparent to one of ordinary skill in the art, withthe exception of operations necessarily occurring in a certain order.Also, descriptions of functions and constructions that are well known toone of ordinary skill in the art may be omitted for increased clarityand conciseness.

The features described herein may be embodied in different forms, andare not to be construed as being limited to the examples describedherein. Rather, the examples described herein have been provided so thatthis disclosure will be thorough and complete, and will convey the fullscope of the disclosure to one of ordinary skill in the art.

In the following description, a first lens refers to a lens closest toan object (or a subject), while a sixth lens refers to a lens closest toan image plane (or an image sensor). Further, a first surface of eachlens refers to a surface of the respective lens that is closest to anobject (or a subject), and a second surface of each lens refers to asurface of the respective lens that is closest to an image plane (or animage sensor). Further, in the present specification, all of radii ofcurvature, thicknesses, OALs (optical axis distances from a firstsurface of the first lens to the image plane), SLs, IMGHs (imageheights), and BFLs (back focus lengths) of the lenses, an overall focallength of an optical system, and a focal length of each lens areexpressed in millimeters (mm). Additionally, thicknesses of lenses, gapsbetween the lenses, OALs, and SLs are distances measured based on anoptical axis of the lenses. Further, in a description for shapes of thelenses, a description of one surface of a lens as being convex meansthat an optical axis portion (e.g., central portion) of thecorresponding surface is convex, and a description of one surface of alens as being concave means that an optical axis portion (e.g. centralportion) of the corresponding surface is concave. Therefore, although itis described that one surface of a lens is convex, an edge portion ofthe lens may be concave. Likewise, although it is described that onesurface of a lens is concave, an edge portion of the lens may be convex.

A lens module includes an optical system including a plurality oflenses. As an example, the optical system of the lens module may includesix lenses having refractive power. However, the lens module is notlimited to only including the six lenses. For example, the lens modulemay include other components that do not have refractive power. As anexample, the lens module may include a stop configured to control anamount of light. As another example, the lens module may further includean infrared cut-off filter configured to filter infrared light. Asanother example, the lens module may further include an image sensor(that is, an imaging device) configured to convert an image of a subject(object) incident thereon through the optical system into electricalsignals. As another example, the lens module may further include a gapmaintaining member configured to adjust a gap between lenses.

First to sixth lenses may be formed of materials having a refractiveindex different from that of air. For example, the first to sixth lensesmay be formed of plastic or glass. At least one of the first to sixthlenses may have an aspherical surface shape. As an example, only thesixth lens of the first to sixth lenses may have the aspherical surfaceshape. As another example, at least one surface of all of the first tosixth lenses may be aspherical. Here, the aspherical surface of eachlens may be represented by the following Equation 1:

$\begin{matrix}{z = {\frac{{cr}^{2}}{1 + \sqrt{1 - {\left( {1 + k} \right)c^{2}r^{2}}}} + {Ar^{4}} + {Br^{6}} + {Cr^{8}} + {Dr^{10}} + {Er^{12}} + {Fr}^{14} + {Gr^{16}} + {Hr^{18}} + {{Jr}^{20}.}}} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

In Equation 1, c is an inverse of a radius of curvature of acorresponding lens, K is a conic constant, and r is a distance from acertain point on an aspherical surface to an optical axis in a directionperpendicular to the optical axis. In addition, constants A to Jsequentially refer to 4th order to 20th order aspheric coefficients. Inaddition, Z is a distance between the certain point on the asphericalsurface at the distance r and a tangential plane meeting the apex of theaspherical surface of the lens.

The optical system configuring the lens module may have a wide field ofview (FOV) of about 78 degrees or more. Therefore, the lens moduleaccording to the example may easily photograph a wide background orobject.

Next, main components configuring the lens module will be described.

The first lens has refractive power. For example, the first lens mayhave negative refractive power.

The first lens may have a meniscus shape. As an example, the first lensmay have a meniscus shape of which a first surface (object-side surface)is convex and a second surface (image-side surface) is concave. Asanother example, the first lens may have a meniscus shape of which thefirst surface is concave and the second surface is convex.

The first lens may have an aspherical surface. For example, the firstand second surfaces of the first lens may be aspherical. The first lensmay be formed of a material having high light transmissivity andexcellent workability. For example, the first lens may be formed ofplastic or glass, but is not limited to these materials.

The second lens has refractive power. For example, the second lens mayhave positive refractive power.

Both surfaces of the second lens may be convex. For example, a firstsurface of the second lens may be convex, and a second surface of thesecond lens may be convex.

The second lens may have an aspherical surface. For example, the firstand second surfaces of the second lens may be aspherical. The secondlens may be formed of a material having high light transmissivity andexcellent workability. For example, the second lens may be formed ofplastic or glass, but is not limited to these materials.

The third lens has refractive power. For example, the third lens mayhave negative refractive power.

At least one surface of the third lens may be concave. As an example, afirst surface of the third lens may be convex and a second surfacethereof may be concave. As another example, the first and secondsurfaces of the third lens may be concave.

The third lens may have an aspherical surface. For example, the firstand second surfaces of the third lens may be aspherical. The third lensmay be formed of a material having high light transmissivity andexcellent workability. For example, the third lens may be formed ofplastic or glass, but is not limited to these materials.

The third lens may be formed of a material having a high refractiveindex. For example, the third lens may be formed of a material having arefractive index of 1.60 or more (in this case, the third lens may havean Abbe number of 30 or less). The third lens formed of this materialmay easily refract light even while having a small curvature. Therefore,the first lens formed of this material may be easily manufactured andmay be advantageous in lowering a defect rate depending on manufacturingtolerance. In addition, the third lens formed of this material maydecrease a distance between lenses, and thus it may be advantageous inminiaturizing the lens module.

The fourth lens has refractive power. For example, the fourth lens mayhave positive refractive power or negative refractive power.

The fourth lens may have a meniscus shape. As an example, the fourthlens may have a meniscus shape of which a first surface is convex and asecond surface is concave. As another example, the fourth lens may havea meniscus shape of which the first surface is concave and the secondsurface is convex.

The fourth lens may have an aspherical surface. For example, the firstand second surfaces of the fourth lens may be aspherical. The fourthlens may be formed of a material having high light transmissivity andexcellent workability. For example, the fourth lens may be formed ofplastic or glass, but is not limited to these materials.

The fifth lens has refractive power. For example, the fifth lens mayhave positive refractive power.

The fifth lens may be convex toward an image side. For example, a firstsurface of the fifth lens may be concave and a second surface thereofmay be convex.

The fifth lens may have an aspherical surface. For example, the firstand second surfaces of the fifth lens may be aspherical. In addition,the fifth lens may have an aspherical surface shape including aninflection point. For example, one or more inflection points may beformed on an image-side surface of the fifth lens.

The fifth lens may be formed of a material having high lighttransmissivity and excellent workability. For example, the fifth lensmay be formed of plastic or glass, but is not limited to thesematerials.

The sixth lens has refractive power. For example, the sixth lens mayhave negative refractive power.

The sixth lens may have a meniscus shape of which an object-side surfaceis convex. For example, a first surface of the sixth lens may be convex,and a second surface of the sixth lens may be concave.

The sixth lens may have an aspherical surface. For example, the firstand second surfaces of the sixth lens may be aspherical. In addition,the sixth lens may have an aspherical surface shape including aninflection point. For example, one or more inflection points may beformed on an object-side surface and an image-side surface of the sixthlens. The first surface of the sixth lens having the inflection pointmay be convex at the center of an optical axis, may be concave in thevicinity of the optical axis, and may again be convex at an edgethereof. In addition, the second surface of the sixth lens may beconcave at the center of an optical axis and become convex at an edgethereof. The sixth lens may be formed of a material having high lighttransmissivity and high workability. For example, the sixth lens may beformed of plastic or glass, but is not limited to these materials.

The image sensor may, for example, realize high resolution of about 1300megapixels. For example, a unit size of the pixels configuring the imagesensor may be about 1.12 μm or less.

The lens module may have a wide field of view. For example, the opticalsystem of the lens module may have a field of view of about 78 degreesor more. In addition, the lens module may have a relatively short length(TTL). For example, an overall length (distance from the object-sidesurface of the first lens to the image plane) of the optical systemconfiguring the lens module may be about 5.10 mm or less.

The optical system of the lens module configured as described above maysatisfy the following Conditional Expression 1:−10<V1−V2<10.  [Conditional Expression 1]

In Conditional Expression 1, V1 is an Abbe number of the first lens, andV2 is an Abbe number of the second lens.

In addition, the optical system of the lens module may satisfy thefollowing Conditional Expression 2:0.6<f5/f.  [Conditional Expression 2]

In Condition Expression 2, f is an overall focal length of the opticalsystem including the first to sixth lenses, and f5 is a focal length ofthe fifth lens.

Conditional Expression 2 may be a necessary condition for correctingaberration and realizing high resolution. For example, in a case inwhich Conditional Expression 2 is not satisfied, refractive power of thefifth lens may be excessively high, and thus an aberration correctioneffect of the optical system may be insufficient, and it may bedifficult to realize high resolution of the optical system. Conversely,in a case in which Conditional Expression 2 is satisfied, it may be easyto correct aberration of the optical system and realize high resolutionof the optical system.

A lens module 100 according to a first example will be described withreference to FIG. 1 .

The lens module 100 includes an optical system including a first lens110, a second lens 120, a third lens 130, a fourth lens 140, a fifthlens 150, and a sixth lens 160. In addition, the lens module 100 furtherincludes an infrared cut-off filter 70 and an image sensor 80. Further,the lens module 100 includes a stop ST. For example, the stop ST may bedisposed between a subject (object) and the first lens 110, as shown inFIG. 1 , or between the first lens 110 and the second lens 120.

In this example, the first lens 110 has negative refractive power, andan object-side surface thereof is concave and an image-side surfacethereof is convex. The second lens 120 has positive refractive power,and an object-side surface thereof is convex and an image-side surfacethereof is convex. The third lens 130 has negative refractive power, andan object-side surface thereof is convex and an image-side surfacethereof is concave. The fourth lens 140 has negative refractive power,and an object-side surface thereof is convex and an image-side surfacethereof is concave. The fifth lens 150 has positive refractive power,and an object-side surface thereof is concave and an image-side surfacethereof is convex. The sixth lens 160 has negative refractive power, andan object-side surface thereof is convex and an image-side surfacethereof is concave. In addition, one or more inflection points areformed on each of the object-side surface and the image-side surface ofthe sixth lens 160.

In the example of FIG. 1 , the first lens 110, the third lens 130, thefourth lens 140, and the sixth lens 160 each have negative refractivepower, as described above. Among these lenses, the first lens 110 mayhave the strongest refractive power, and the sixth lens 160 may have theweakest refractive power.

In the example of FIG. 1 , a value of V1−V2 from Conditional Expression1 is 0, and a value of f5/f from Conditional Expression 2 is 0.620.

FIGS. 2A and 2B are graphs having curves which represent aberrationcharacteristics of the lens module 100.

FIG. 3 is a table representing characteristics of the lenses 110, 120,130, 140, 150 and 160 configuring the lens module. In FIG. 3 , SurfaceNos. 1 and 2 indicate the first surface (object-side surface) and thesecond surface (image-side surface), respectively, of the first lens110, and Surface Nos. 3 and 4 indicate the first and second surfaces,respectively, of the second lens 120. Similarly, Surface Nos. 5 to 12indicate first and second surfaces of the third to sixth lenses 130 to160, respectively. In addition, Surface Nos. 13 and 14 indicate firstand second surfaces, respectively, of the infrared cut-off filter 70.

FIG. 4 is a table representing conic constants and aspheric coefficientsof the lenses 110, 120, 130, 140, 150 and 160 configuring the lensmodule 100. In FIG. 4 , numbers 1 to 12 in the first column of the tableindicate Surface Nos. of the first to sixth lenses 110 to 160.

A lens module 200 according to a second example will be described withreference to FIG. 5 .

The lens module 200 includes an optical system including a first lens210, a second lens 220, a third lens 230, a fourth lens 240, a fifthlens 250, and a sixth lens 260. In addition, the lens module 200includes an infrared cut-off filter 70, an image sensor 80 and a stopST. For example, the stop ST may be disposed between an object and thefirst lens 210, as shown in FIG. 5 , or between the first lens 210 andthe second lens 220.

In this example, the first lens 210 has negative refractive power, andan object-side surface thereof is concave and an image-side surfacethereof is convex. The second lens 220 has positive refractive power,and an object-side surface thereof is convex and an image-side surfacethereof is convex. The third lens 230 has negative refractive power, andan object-side surface thereof is concave and an image-side surfacethereof is concave. The fourth lens 240 has negative refractive power,and an object-side surface thereof is concave and an image-side surfacethereof is convex. The fifth lens 250 has positive refractive power, andan object-side surface thereof is concave and an image-side surfacethereof is convex. The sixth lens 260 has negative refractive power, andan object-side surface thereof is convex and an image-side surfacethereof is concave. In addition, one or more inflection points areformed on each of the object-side surface and the image-side surface ofthe sixth lens 260.

In the example of FIG. 5 , first lens 210, the third lens 230, thefourth lens 240, and the sixth lens 260 each have negative refractivepower, as described above. Among these lenses, the first lens 210 mayhave the strongest refractive power, and the sixth lens 260 may have theweakest refractive power.

In the example of FIG. 5 , a value of V1−V2 from Conditional Expression1 is 0, and a value of f5/f from Conditional Expression 2 is 0.721.

FIGS. 6A and 6B are graphs having curves which represent aberrationcharacteristics of the lens module 200.

FIG. 7 is a table representing characteristics of the lenses 210, 220,230, 240, 250 and 260 configuring the lens module 200. In FIG. 7 ,Surface Nos. 1 and 2 indicate the first surface (object-side surface)and the second surface (image-side surface), respectively, of the firstlens 210, and Surface Nos. 3 and 4 indicate the first and secondsurfaces, respectively, of the second lens 220. Similarly, Surface Nos.5 to 12 indicate first and second surfaces of the third to sixth lenses230 to 260, respectively. In addition, Surface Nos. 13 and 14 indicatefirst and second surfaces, respectively of the infrared cut-off filter70.

FIG. 8 is a table representing conic constants and aspheric coefficientsof the lenses 210, 220, 230, 240, 250 and 260 configuring the lensmodule 200. In FIG. 8 , numbers 1 to 12 in the first column of the tableindicate Surface Nos. of the first to sixth lenses 210 to 260.

A lens module 300 according to another example will be described withreference to FIG. 9 .

The lens module 300 includes an optical system including a first lens310, a second lens 320, a third lens 330, a fourth lens 340, a fifthlens 350, and a sixth lens 360. In addition, the lens module 300 furtherincludes an infrared cut-off filter 70, an image sensor 80 and a stopST. For example, the stop ST may be disposed between an object and thefirst lens 310, as shown in FIG. 9 , or between the first lens 310 andthe second lens 320.

In this example, the first lens 310 has negative refractive power, andan object-side surface thereof is convex and an image-side surfacethereof is concave. The second lens 320 has positive refractive power,and an object-side surface thereof is convex and an image-side surfacethereof is convex. The third lens 330 has negative refractive power, andan object-side surface thereof is convex and an image-side surfacethereof is concave. The fourth lens 340 has positive refractive power,and an object-side surface thereof is convex and an image-side surfacethereof is concave. The fifth lens 350 has positive refractive power,and an object-side surface thereof is concave and an image-side surfacethereof is convex. The sixth lens 360 has negative refractive power, andan object-side surface thereof is convex and an image-side surfacethereof is concave. In addition, one or more inflection points areformed on each of the object-side surface and the image-side surface ofthe sixth lens 360.

In the example of FIG. 9 , the first lens 310, the third lens 330, thefourth lens 340, and the sixth lens 360 each have negative refractivepower, as described above. Among these lenses, the first lens 310 mayhave the strongest refractive power, and the sixth lens 360 may have theweakest refractive power.

In the example of FIG. 9 , a value of V1−V2 from Conditional Expression1 is 0, and a value of f5/f from Conditional Expression 2 is 0.625.

FIGS. 10A and 10B are graphs having curves which represent aberrationcharacteristics of the lens module 300.

FIG. 11 is a table representing characteristics of the lenses 310, 320,330, 340, 350, 360 configuring the lens module 300. In FIG. 11 , SurfaceNos. 1 and 2 indicate the first surface (object-side surface) and thesecond surface (image-side surface) of the first lens 310, and SurfaceNos. 3 and 4 indicate the first and second surfaces, respectively, ofthe second lens 320. Similarly, Surface Nos. 5 to 12 indicate first andsecond surfaces of the third to sixth lenses 330 to 360, respectively.In addition, Surface Nos. 13 and 14 indicate first and second surfaces,respectively of the infrared cut-off filter 70.

FIG. 12 is a table representing conic constants and asphericcoefficients of the lenses 310, 320, 330, 340, 350, 360 configuring thelens module 300. In FIG. 12 , numbers 1 to 12 in the first column of thetable indicate Surface Nos. of the first to sixth lenses 310 to 360.

A lens module 400 according to a fourth example will be described withreference to FIG. 13 .

The lens module 400 includes an optical system including a first lens410, a second lens 420, a third lens 430, a fourth lens 440, a fifthlens 450, and a sixth lens 460. In addition, the lens module 400 furtherincludes an infrared cut-off filter 70, an image sensor 80 and a stopST. For example, the stop ST may be disposed between an object and thefirst lens 410, as shown in FIG. 13 , or between the first lens 410 andthe second lens 420.

In this example, the first lens 410 has negative refractive power, andan object-side surface thereof is convex and an image-side surfacethereof is concave. The second lens 420 has positive refractive power,and an object-side surface thereof is convex and an image-side surfacethereof is convex. The third lens 430 has negative refractive power, andan object-side surface thereof is concave and an image-side surfacethereof is concave. The fourth lens 440 has positive refractive power,and an object-side surface thereof is convex and an image-side surfacethereof is concave. The fifth lens 450 has positive refractive power,and an object-side surface thereof is concave and an image-side surfacethereof is convex. The sixth lens 460 has negative refractive power, andan object-side surface thereof is convex and an image-side surfacethereof is concave. In addition, one or more inflection points areformed on each of the object-side surface and the image-side surface ofthe sixth lens 460.

In this example, the first lens 410, the third lens 430, the fourth lens440, and the sixth lens 460 each have negative refractive power, asdescribed above. Among these lenses, the first lens 410 may have thestrongest refractive power, and the sixth lens 460 may have the weakestrefractive power.

In the example of FIG. 13 , a value of V1−V2 from Conditional Expression1 is 0, and a value of f5/f from Conditional Expression 2 is 0.7310.

FIGS. 14A and 14B are graphs having curves which represent aberrationcharacteristics of the lens module.

FIG. 15 is a table representing characteristics of the lenses 410, 420,430, 440, 450 and 460 configuring the lens module 400. In FIG. 15 ,Surface Nos. 1 and 2 indicate the first surface (object-side surface)and the second surface (image-side surface) of the first lens 410, andSurface Nos. 3 and 4 indicate the first and second surfaces,respectively, of the second lens 420. Similarly, Surface Nos. 5 to 12indicate first and second surfaces of the third to sixth lenses 430 to460, respectively. In addition, Surface Nos. 13 and 14 indicate firstand second surfaces, respectively, of the infrared cut-off filter 70.

FIG. 16 is a table representing conic constants and asphericcoefficients of the lenses 410 to 460 configuring the lens module 400.In FIG. 16 , numbers 1 to 12 in the first column of the table indicateSurface Nos. of the first to sixth lenses 410 to 460.

TABLE 1 Lens Module Lens Module Lens Module Lens Module Remark 100 200300 400 f (EFL) 3.4870 2.8390 3.4510 2.9860 f1 −102.18 −17.90 −200.00−200.00 f2 2.3540 1.6960 2.5010 2.2680 f3 −3.9030 −2.9500 −4.0470−3.1190 f4 −240.778 −162.123 27.043 17.429 f5 2.1630 2.0460 2.15802.1830 f6 −2.0470 −2.1810 −1.9820 −2.3980 TTL 5.0727 4.5950 4.92754.6015 FOV 78.716 90.422 79.300 87.531

Table 1 above represents optical characteristics of the lens modules100-400 according to the examples disclosed herein. The lens module mayhave an overall focal length (f) of about 2.70 to about 3.60. A focallength (f1) of the first lens may be determined to be in a range ofabout −210 to about −16.0. A focal length (f2) of the second lens may bedetermined to be in a range of about 1.50 to about 2.70. A focal length(f3) of the third lens may be determined to be in a range of about −5.0to about −2.0. A focal length (f4) of the fourth lens may be determinedto be in a range of about −250 to about 30.0. A focal length (f5) of thefifth lens may be determined to be in a range of about 1.80 to about2.40. A focal length (f6) of the sixth lens may be determined to be in arange of about −3.0 to about −1.50. An overall length of the opticalsystem may be determined to be in a range of about 4.40 to about 5.20. Afield of view (FOV) of the lens module may be in a range of about 77.0to about 93.0.

As set forth above, according to the disclosed examples, the opticalsystem may have high resolution.

While this disclosure includes specific examples, it will be apparent toone of ordinary skill in the art that various changes in form anddetails may be made in these examples without departing from the spiritand scope of the claims and their equivalents. The examples describedherein are to be considered in a descriptive sense only, and not forpurposes of limitation. Descriptions of features or aspects in eachexample are to be considered as being applicable to similar features oraspects in other examples. Suitable results may be achieved if thedescribed techniques are performed in a different order, and/or ifcomponents in a described system, architecture, device, or circuit arecombined in a different manner, and/or replaced or supplemented by othercomponents or their equivalents. Therefore, the scope of the disclosureis defined not by the detailed description, but by the claims and theirequivalents, and all variations within the scope of the claims and theirequivalents are to be construed as being included in the disclosure.

What is claimed is:
 1. A lens module comprising: a first lens havingnegative refractive power; a second lens having positive refractivepower and a convex object-side surface; a third lens having negativerefractive power and a convex object-side surface; a fourth lens havingnegative refractive power, a convex object-side surface, and a concaveimage-side surface; a fifth lens having a refractive power; and a sixthlens having one or more inflection points on an image-side surfacethereof, wherein the first to sixth lenses are sequentially disposedfrom an object side of the lens module to an image side of the lensmodule, wherein an absolute value of a radius of curvature of theobject-side surface of the second lens is less than an absolute value ofa radius of curvature of an object-side surface of the first lens, andwherein −10<V1−V2<10, where V1 is an Abbe number of the first lens andV2 is an Abbe number of the second lens.
 2. The lens module of claim 1,wherein the first lens has a convex image-side surface.
 3. The lensmodule of claim 1, wherein the second lens has a convex image-sidesurface.
 4. The lens module of claim 1, wherein the third lens has aconcave image-side surface.
 5. The lens module of claim 1, wherein thefourth lens has negative refractive power.
 6. The lens module of claim1, wherein the fifth lens has positive refractive power.
 7. The lensmodule of claim 1, wherein the fifth lens has a concave object-sidesurface.
 8. The lens module of claim 1, wherein the fifth lens has aconvex image-side surface.
 9. The lens module of claim 1, wherein thesixth lens has negative refractive power.
 10. The lens module of claim1, wherein the sixth lens has a convex object-side surface.
 11. The lensmodule of claim 1, wherein the sixth lens has a concave image-sidesurface.
 12. The lens module of claim 1, wherein 0.6<f5/f, where f5 is afocal length of the fifth lens and f is an overall focal length of thelens module.
 13. The lens module of claim 1, wherein −210 mm<f1 <−16.0mm, where f1 is a focal length of the first lens.
 14. The lens module ofclaim 1, wherein 1.50 mm <f2 <2.70 mm, where f2 is a focal length of thesecond lens.
 15. The lens module of claim 1, wherein −5.00 mm <f3 <−2.00mm, where f3 is a focal length of the third lens.